This invention relates to certain novel N-phenyl p-phenylene diamino derivatives and their use as stabilizers in rubber or rubber latex. Compounds of the general formula: ##STR2## wherein R' represents an aryl group, R" an arylene group and Y a carboxy substituted alkyl group have already been described in U.S. Pat. No. 2,266,602. The compounds mentioned therein can all be characterized by the following, more specific formula: ##STR3## wherein Y' has the meaning of, for instance, a hydroxyl group, an --O--metal group, an --O--ammonium group, an alkoxy group, an --NH.sub.2 group or an aryloxy group. Such compounds are recommended for use as antioxidants, for instance, in rubber. It has been found that although the compounds described in said patent constitute particularly valuable stabilizers in rubber or rubber latex, they exhibit the tendency to migrate from rubber vulcanizates and to cause discoloration of light colored rubbers, and enamelled or plastic objects upon contact with the vulcanizates. Moreover, such compounds are found to offer relatively little protection from ozone attack.